Fair Value Measurements - Fair Value of Life Policy Loans, Deferred Annuities, and Structured Settlements (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	$ 40	$ 39
Liabilities Related to Investment Contracts, Fair Value Disclosure	714	744
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	0	0
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	0	0
Liabilities Related to Investment Contracts, Fair Value Disclosure	137	141
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	40	39
Liabilities Related to Investment Contracts, Fair Value Disclosure	577	603
Deferred annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	577	603
Deferred annuities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Deferred annuities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Deferred annuities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	577	603
Structured settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	137	141
Structured settlements | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Structured settlements | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	137	141
Structured settlements | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	$ 0	$ 0